Looking to the planets can give us tremendous insight about our future on Earth, climate scientists said last night at the Boulder Theater's "Climate Change on Earth and Other Planets." A bow tie-clad Bill Nye the Science Guy led the panel of four distinguished scientists with a keynote speech, hooking the already lively crowd with the same genuine charm and humor he brought to his self-titled TV show in the mid-'90s.

Nye's show catered to a group of individuals we might now call the climate generation. Earth's human population hit seven billion last October (that number has more than doubled in the lifetimes of many earthlings), which created a rude awakening for those who weren't already aware of the expanding population's inevitable impact on this planet, its atmosphere and its climate.

The evening's series of short lectures on climate change was part of the Lunar and Planetary Institute's four-day Comparative Climatology of Terrestrial Planets meeting in Boulder, and whether drawn to the science or the Science Guy himself, people packed the Boulder Theater last night to "share in the joy of discovery," as Nye put it.

"We didn't know if anyone would be here," said David Grinspoon, panelist and Curator of Astrobiology at the Denver Museum of Nature, adding that it was great to see so much interest in "stuff that we [scientists] obsess about."

In his lecture, Grinspoon raised large-scale questions about sustaining life on Earth far beyond the scope of our lifetimes, pondering topics like the prevention of future ice ages and how we'll deal with the sun as it nears its expiration date.

Other panelists explored topics ranging from acid rain to terraforming Mars, all within the theme of climate change on Earth and other planets. A wildfire that began in Boulder County yesterday brought a local flare to James Hansen's lecture on "The Venus Syndrome," as he touched on how temperature anomalies are causing wildfires to be more frequent, more destructive, and to burn hotter. "The smoke in the room just adds another dimension," Nye said, referring to the campfire smell that permeated the building from the recently ignited Flagstaff fire.

Karen Rice lectures on acidification.

Hansen, who leads NASA's Goddard Institute for Space Studies, also described how human addiction to fossil fuels has shifted Earth's climate. "The climate dice are now loaded," he said. Research hydrologist Karen Rice piled on the human-impact theme, saying that "almost everything we as humans do results in acidification [of the planet," and joking that what Earth really needs is a Rolaid.

Brian Toon, founding chair of the Department of Atmospheric and Oceanic Sciences at the University of Colorado, compared the climates of Venus, Mars and Earth through the metaphor of Goldilocks, explored how Venus and Mars developed to be too hot and too cold to support life while Earth is "just right" in the habitable zone. Toon is interested in the search for parallels between Earth and terrestrial planets -- for those who didn't take Astronomy 101, "terrestrial" describes those solid, inner planets like ours -- and showed how similar processes control the climates of Venus, Mars and Earth, reflecting on the notion that turning our eyes from Earth to other planets might provide clues about our climate's future.

It's easy to forget that Earth isn't alone out there in the solar system -- but fortunately, there are ample reminders out there. For further opportunities to nerd out this summer, tune into the Planetary Society's Planetfest 2012, celebrating the landing of Curiosity, the Mars Science Laboratory, on Mars August 4 to 5.